33 research outputs found
Causal relationship between gut microbiota and myasthenia gravis: a two-sample Mendelian randomization study
BackgroundPrevious observational studies have provided cumulative data linking gut microbiota to myasthenia gravis (MG). However, the causal link between the two remains unexplored. Hence, the current study was performed to explore the causal link between them.MethodsMendelian randomization (MR) analysis was conducted using the summary statistics of 211 gut microbiota taxa and the largest genome-wide association studies (GWAS) for MG currently available. The inverse variance-weighted (IVW), MR-Egger, weighted median, and weighted mode methods were employed to ascertain the causal influence. Sensitivity studies utilizing several methodologies were then used to assess the robustness of the findings. Lastly, to evaluate reverse causality, a reverse MR analysis was performed.ResultsSeven suggestive causal associations between the gastrointestinal microbiota and MG were identified based on the outcomes of the MR analysis. Specifically, phylum Actinobacteria (OR: 0.602, 95% CI: 0.405–0.896, p = 0.012), class Gammaproteobacteria (OR: 0.587, 95% CI: 0.357–0.968, p = 0.037), and families Defluviitaleaceae (OR: 0.695, 95% CI: 0.485–0.996, p = 0.047), Family XIII (OR: 0.614, 95% CI: 0.412–0.916, p = 0.017), and Peptococcaceae (OR: 0.698, 95% CI: 0.505–0.964, p = 0.029) had suggestive protective effects on MG, while order Mollicutes RF9 (OR: 1.424, 95% CI: 1.015–1.998, p = 0.041) and genus Faecalibacterium (OR: 1.763, 95% CI: 1.220–2.547, p = 0.003) were suggestive risk factors for MG. The outcomes indicate that neither heterogeneity nor horizontal pleiotropy had any discernible impact. Nevertheless, this reverse analysis did not reveal any apparent effect of MG on the gut microbiota composition.ConclusionThe MR investigation has substantiated the suggestive causal connection between gut microbiota and MG, which may provide helpful insights for innovative therapeutic and preventative approaches for MG. Further randomized controlled trials are needed to elucidate the gut microbiota’s precise role and therapeutic potential in the pathogenesis of MG
Fair Federated Medical Image Segmentation via Client Contribution Estimation
How to ensure fairness is an important topic in federated learning (FL).
Recent studies have investigated how to reward clients based on their
contribution (collaboration fairness), and how to achieve uniformity of
performance across clients (performance fairness). Despite achieving progress
on either one, we argue that it is critical to consider them together, in order
to engage and motivate more diverse clients joining FL to derive a high-quality
global model. In this work, we propose a novel method to optimize both types of
fairness simultaneously. Specifically, we propose to estimate client
contribution in gradient and data space. In gradient space, we monitor the
gradient direction differences of each client with respect to others. And in
data space, we measure the prediction error on client data using an auxiliary
model. Based on this contribution estimation, we propose a FL method, federated
training via contribution estimation (FedCE), i.e., using estimation as global
model aggregation weights. We have theoretically analyzed our method and
empirically evaluated it on two real-world medical datasets. The effectiveness
of our approach has been validated with significant performance improvements,
better collaboration fairness, better performance fairness, and comprehensive
analytical studies.Comment: Accepted at CVPR 202
Integrating life cycle assessment and a farmer survey of management practices to study environmental impacts of peach production in Beijing, China
Moir\'e Fractional Chern Insulators II: First-principles Calculations and Continuum Models of Rhombohedral Graphene Superlattices
The experimental discovery of fractional Chern insulators (FCIs) in
rhombohedral pentalayer graphene twisted on hexagonal boron nitride (hBN) has
preceded theoretical prediction. Supported by large-scale first principles
relaxation calculations at the experimental twist angle of , we
obtain an accurate continuum model of layer rhombohedral
graphene-hBN moir\'e systems. Focusing on the pentalayer case, we analytically
explain the robust Chern numbers seen in the low-energy
single-particle bands and their flattening with displacement field, making use
of a minimal two-flavor continuum Hamiltonian derived from the full model. We
then predict nonzero valley Chern numbers at the insulators
observed in experiment. Our analysis makes clear the importance of displacement
field and the moir\'e potential in producing localized "heavy fermion" charge
density in the top valence band, in addition to the nearly free conduction
band. Lastly, we study doubly aligned devices as additional platforms for
moir\'e FCIs with higher Chern number bands.Comment: Second paper in the moir\'e FCI serie
Beam test of a 180 nm CMOS Pixel Sensor for the CEPC vertex detector
The proposed Circular Electron Positron Collider (CEPC) imposes new
challenges for the vertex detector in terms of pixel size and material budget.
A Monolithic Active Pixel Sensor (MAPS) prototype called TaichuPix, based on a
column drain readout architecture, has been developed to address the need for
high spatial resolution. In order to evaluate the performance of the
TaichuPix-3 chips, a beam test was carried out at DESY II TB21 in December
2022. Meanwhile, the Data Acquisition (DAQ) for a muti-plane configuration was
tested during the beam test. This work presents the characterization of the
TaichuPix-3 chips with two different processes, including cluster size, spatial
resolution, and detection efficiency. The analysis results indicate the spatial
resolution better than 5 and the detection efficiency exceeds 99.5 %
for both TaichuPix-3 chips with the two different processes
Mass testing of the JUNO experiment 20-inch PMTs readout electronics
The Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose,
large size, liquid scintillator experiment under construction in China. JUNO
will perform leading measurements detecting neutrinos from different sources
(reactor, terrestrial and astrophysical neutrinos) covering a wide energy range
(from 200 keV to several GeV). This paper focuses on the design and development
of a test protocol for the 20-inch PMT underwater readout electronics,
performed in parallel to the mass production line. In a time period of about
ten months, a total number of 6950 electronic boards were tested with an
acceptance yield of 99.1%
Implementation and performances of the IPbus protocol for the JUNO Large-PMT readout electronics
The Jiangmen Underground Neutrino Observatory (JUNO) is a large neutrino
detector currently under construction in China. Thanks to the tight
requirements on its optical and radio-purity properties, it will be able to
perform leading measurements detecting terrestrial and astrophysical neutrinos
in a wide energy range from tens of keV to hundreds of MeV. A key requirement
for the success of the experiment is an unprecedented 3% energy resolution,
guaranteed by its large active mass (20 kton) and the use of more than 20,000
20-inch photo-multiplier tubes (PMTs) acquired by high-speed, high-resolution
sampling electronics located very close to the PMTs. As the Front-End and
Read-Out electronics is expected to continuously run underwater for 30 years, a
reliable readout acquisition system capable of handling the timestamped data
stream coming from the Large-PMTs and permitting to simultaneously monitor and
operate remotely the inaccessible electronics had to be developed. In this
contribution, the firmware and hardware implementation of the IPbus based
readout protocol will be presented, together with the performances measured on
final modules during the mass production of the electronics
Validation and integration tests of the JUNO 20-inch PMTs readout electronics
The Jiangmen Underground Neutrino Observatory (JUNO) is a large neutrino
detector currently under construction in China. JUNO will be able to study the
neutrino mass ordering and to perform leading measurements detecting
terrestrial and astrophysical neutrinos in a wide energy range, spanning from
200 keV to several GeV. Given the ambitious physics goals of JUNO, the
electronic system has to meet specific tight requirements, and a thorough
characterization is required. The present paper describes the tests performed
on the readout modules to measure their performances.Comment: 20 pages, 13 figure
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
Robust estimation of bacterial cell count from optical density
Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data